Several computer systems in a local area network (LAN) may be joined together by a single component commonly referred to as a hub. The hub typically serves as common network termination point for multiple computer systems, as is shown in FIG. 1.
The computer systems provided in the LAN (otherwise referred to as Nodes, when interconnected to a hub) may communicate with each other via the hub. For example, node 12 may send a signal addressed to node 14. The signal will first be transmitted from the node 12 to the hub 10. The signal will then be transmitted from the hub to node 14.
The hub 10 may also provide the nodes with access to other separate LANs. That is, the hub 10 may be connected with a cable which is connected to a separate second hub, which provides access to a second LAN. As a result, the nodes attached to hub 10 can also send messages and signals to the second LAN via the hub 10.
A network architecture commonly implemented using a hub is referred to as the token ring architecture. The token ring network architecture uses a ring network topology and a token-passing strategy to control access to the network.
A single token ring implemented in a hub may be extended into a larger token ring by joining two or more hubs. The technique of joining multiple hubs is sometimes referred to as cascading. In the prior art, however, the interconnecting of multiple hubs may only be used to extend a single token ring.
On the other hand, additional intelligence may be implemented on the hub 10 to support multiple separate LANs (i.e., separate token rings). In such a case, the hub is referred to a multi-ring hub. For example, in FIG. 1, if hub 10 is a multi-ring hub, nodes 12 and 14 may makeup a first token ring, while nodes 14 and 18 may provide a second token ring.
However, the prior art does not provide a method for extending multiple token rings by joining a set of multi-ring hubs. As such, there is a need for a method and apparatus of extending multiple separate token rings by cascading multi-ring hubs.